PIPE AS-AFTCLR 3755620 - Caterpillar

ACTION REQUIRED
After failure replace the oil cooler per SENR6564, Disassembly and Assembly. Then use the Rework Procedure to identify the appropriate failure. This service letter only applies for a failure as described in the attached Rework Procedure.
SERVICE CLAIM ALLOWANCES
Product smu/age whichever comes first Caterpillar Dealer Suggested Customer Suggested
Parts % Labor Hrs% Parts % Labor Hrs% Parts % Labor Hrs%
0-10000 hrs,
0-24 mo 100.0% 100.0% 0.0% 0.0% 0.0% 0.0%
This is a 5.7-hour job
PARTS DISPOSITION
Handle the parts in accordance with your Warranty Bulletin on warranty parts handling.
Rework Procedure
Analysis of most recent oil cooler failures indicate that the cooler bundle assembly may have partially collapsed. A collapsed bundle or tube could have been damaged enough to cause a early hour leak failure of the tube that will allow the coolant and oil to mix. Example of a collapsed bundle is shown below:
MATERIAL REQUIRED
Steel Rod
Diameter: 5/32 inch or 4mm
Length:48"
Reference: McMaster Carr Part Number
8888K236 (Inch) ? 72" long
8116K86 (Metric) ? 72" long
48 inches of clearance from face of cooler after removal of bonnet for rod insertion
Oil Cooler part number: 373-6537 and 10R-5667
Duct Tape
Image1.2.1
PROCEDURE
Cut steel rod to length: 1200 mm (48")
Use tape to mark 1080 mm (42.5") from one end of the rod
Slowly insert the rod into tubes marked by green dots (center of the tube bundle) shown in Image 1.3.1 in order to obtain feel for good tube.
Slowly insert the rod into tubes marked by red dots (top and bottom of the tube bundle) shown in Image 1.3.1.
The rod should be able to be inserted with little or no resistance (less than 22 N or 5 lbs). Do not force the rod into the tube if it stops before reaching the full length (1080 mm) indicated by the tape on the rod.
Image1.3.1
If the rod can be fully inserted into all marked tubes in red (top and bottom of the tube bundle), then the tube bundle is not collapsed.
If the rod cannot be fully inserted into all the marked tubes in red (top and bottom of the tube bundle, then it is likely that the oil cooler has a collapsed bundle.